Light sensitive material for the photomechanical preparation of printing plates



United States Patent 38 Claims. iol. 96-33) In presensitized material useful for the photo-mechanical preparation of printing plates, the'o-quinone diazides and p-quinone diazides, including in particular those substituted in the nucleus by su1fonic acid ester or sulfonamide groups, have attai'neclindxistrial importance, and also the iminoquinone diazides. As a result of the pronounced light-sensitivity thereof, imiiioquinone diazides of the benzene series, derived from a "1,4-phenylene diamine substituted in -an-aminogroup by an aryl sulfonyl radical, which together withother imihoquinone diazides are described in German Patent 901,500, have proved very satisfactory. When exposed to light, the iminoquinone diazides are converted to products of high molecular Weight which are more difficultly soluble in dilute alkalis, dilute acids or organic solvents than are the iminoquinone diazides themselves. T his property provides the basis for the suitability of -these compounds for the production of images and the preparation of printing plates since, after reproduction coatings prepared therewith have been exposed under a master to light, the remaining light-sensitive portion can be selectively separated from the light-decomposition l'tproduct using the developers described above. From a negative original, positive images or printing plates are obtained, and vice versa.

In further work on iminoquinone diazides as lightsensitive compounds, a reproduction material containing iminoquinone diazides in the coating has been found which is particularly suitable for the preparation of images or printing plates. In this material, the iminoquinone diazides which constitute the reproduction coating, or which are contained therein, correspond to the general formula liq-50 R sulfarnine radical substituted in the amino group and attached in the ortho position-toth'e aryl snlfonyl radical. The technical advance involved in the use of the iminoquinone diazides corresponding to the general formula given above resides in the greater stability of these compounds, as it is considerably greater than that of the Patefited Mar. 30, 1965 iminoquinone diazides described in German Patent 901,- 500. The reproduction material of the invention is thus a light-sensitive material with excellent shelf life from which very stable inia'ges-andhprinting'plates giving very long runs can be'prepared.

The stabilizing effect resulting from thei sulfamine radical substituted in the amino group, when in the ortho position to an aryl sulfonylimino radical, is accompanied by a loss in light-sensitivity, in comparison with the iminoquinone diazide compounds without the sulfamine radical. However, this eitectonthe light-sensitivity can be compensated for by the introduction of electro-negative substituents such as halogehfieflkoxyl, alkyl, and the like into the nucleus of the aryl-sulfonylimino radical or into the sulfarnineqadical or-intoboth, without the stability of the compoundsbeing influenced.

Exemplary of the compounds of the invention are:

is. i.

(Formula-2,)

(Forf mula 27) OICH (Formula 21) (Formula 28 I 5 0 r-N- C 3 1 (Formula 22) (Formula 29) (Formula 30) (Formula 25) '2 (Formula 32) (Formula 40) (Formula 33) (Formula 34) (Formula 41 O CH;

(Formula 35) (Formula 42) (Formula 36) CH; $11 5H3 (Formula 43) m 3 .10 H a O H 0 c a i m S O V 5 0 5 6 m C a V H h Q 0 7 3 1 a C m m B N 0 W m S (Formula 44) (Formula 38) m C O H m IJUIC i m S O 1m a i m s O (Formula 46) (Formula 3 (Formula 47) 1 S O r-N Oll -Q (Formula 54) (Formula 48) (Formula 49) (Formula :55)

(Formula 50) 1 (Formula-:56!)

m 0 w w m 7 (Formula 62) (Formula 57) (Formula 63) (Formula 64) (Formula 65) (Formula 66) (Formula 58) (Formula 59) (Formula 60) (Formula 61) is (Formula 67) l i l C H ll 1 (Formula 69) The iminoquinone diazides of the invention. are, for practical purposes, insoluble in water. but are soluble in organic solvents. They are applied in .known manner, in solution in organic solvents, to suitable supports, e.g., metal plates or metal foils, preferably aluminum or. zinc, or paper. It can be advantageous if resins, preferably alkali-soluble resins, are-applied in associationwith the light-sensitive compounds to .the surface of the supports. They favor film-formation and increase the adherence of the image, i.e., the printing image remaining on the support after the development of the exposedreproduction coatin because the light reaction productsof the iminoquinone diazides react with the resins which are. capable of being anchored to the supports. Forexample, the .phenolformaldehyde resin novolaks commercially available under the registered trademark Alnovol and the conversion productsobtained therefrom by etherification With chloroacetic acid have proved tobe very suitable resins for this purpose. Processes of preparation for these etherification products are described in detail in German patent spec. No. 1,053,930, in Example 5.

For specialefiects, e.g., to pr-event crystallization in the reproduction coating and/onto increase resistance to the sensitive substance.

ll development process can bebetterfollowed. -Dyestulf additions do not interfere in any way with the process,

because -it is only with the light-decompositionproducts that the dyestuffs form:precipitation'products during .de-

velopmentwhich are insoluble and not withcthe light- Here, .too, dilute. alkalis are suitable as developers, e.g., solutions of alkali metal salts of phosphoric acid and the alkali metal .salts of :the various forms of silicicacid. Organic bases,.,e. g., the ethanolamines,.in theform of aqueoussolutions thereofmayalso be used as developers. In the case of'development with solutions containing alkali silicate, .water-conduction -in the image-free partsof the surface of "the support is ade- .quate after the alkaline treatment, so that further treatmentwith diluteacids, such as is usually performed in the printing trade is not necessary. I

The ili'ghtsdecornposition products of the iminoquinone diazides of the invention are characterized by excellent oleophilic properties and they acceptagreasy ink with great facility. This is of great technical importance because the printing plates once readyfor'printing will give full-value copies after only-a-few turns of .the roller of the rotary printing-machine.

-Notonly is the reproduction material of the :invention of exceptional suitability for the preparation of plan0 graphic printing plates'ybut, also, because of-the;-greater resistance of the light-decomposition productsto acids, the surface of the supporteanbe-etched, e.g., with nitric acid, after development and,stencils suitable for relief printing thereby prepared.

The iminoquinone diazidesfiorresponding .to the.formula given above are obtainedbythe following processes: (1) 1-chloro-4vnitro-benzenee2ssulfochloride is reacted withan aromaticj base, as-a result of which the 1-chloro- 4-nitro-benzene-2-sulfarylamides .are formed. .IThese in- 'termediate products are condensed in solv'entswith aryl sulfonamides, inthe presence .of copper powderand alkali carbonate. The chlorine in the one position isthus .replaced by the aryl sulfonamide residue. The .nitrocompounds obtained. canbe'reduced-by known processes, e.g., by means of sodium .dithionite, and the amines thus obtained are diazotized in water-miscible solvents, e.g., in. a mixture of dimethyl formamide and glacial acetic acid. The irninoquinone diazides, for. the most part, precipitate out in the form of .sparinglysoluble compounds, or they can be precipitated by the addition of water.

(2) 4-nitro-1famine-benzene-Z-sulfonic acid is reacted with aromatic sulfochlorides and the l-aryl-sulfaminoe4- nitro-2-benzene-sulfonic acids thus obtained. are converted into sulfochlorides which are then reacted with aromatic bases. The nitro compounds thus obtained are further I processed-as ,described above under (1).

The list below gives In Column 1the number of the compound in the formula list above,

In Column 2-the R constituent,

In Column 3-the constituent,

In Column 4the=R' constituent,

In Column 5thedecompositionpoint of the iminoquinone diazide, and

In Column 6the mostadvantageous developer forareproduction coating containing the iminoqui none diazide inquestion as the light-sensitive substance. Columntfi gives the percentage content of active substance in the aqueousdeveloper, the .letter A standing for sodium metasilicate and B fortrisodium phosphate.

a, 1 75 ,so a e s 33 J3. 3

4methyl-phenyl 2,E-dimethyl-phenyl-amino 175 0 1% A. 2,4,6-tri1nethyl-pheuyl. 4-methoxy-phenyl-amino. 154-156" C. 1% B and 0.3% A. 2,4-dichloro-pheny1 (1 150-152 C 4methyl-pheny1 163-165 C- 1.52% B and 0.3% 2,4,5-trimethyl-phenyl. A-chloro-phenyl-amino- ISO-140 O 1% 4-chloro-phenyl 4-methoxy-phenyl-amino- 1.5% B. Phenyl Phenyl-ethyl-amino 1% B. 41nethyl-phenyl Phenyl-amino. 0.25% B. Phcnyl. 0.5% B. 4-c hlor0-pheny1 0.5% 13. Phenyl. 0.25% B. 2-chloro-4-meth0xy-phenyl-amino. 0.5% B. 3-chloro-phenyl-amino. 0.5% B. d0 do 0.5%]3. 4-methy1-phenyL 1% B. 4methoxy=pheny1 1% B.

d 0.5% B. 2,4-dicliloro-phenyl-ainino. 108 C 0.5% B. B-napthyl-amino. -160-190 1% B. 4-methoxy-phenyl-amino 155-156 C 0.5% B. lropylnmino. 156158 O 0.5% B. o n-Butyl-amino 151-152 C- 0.5% B. A-chloro-phenyl- 4-ch1oro-phenyl-an 178180 C 1% B. 4-m0thyl-pl1enyl 0 a. 170 C 1% B. Phenyl Isobutylnmrno -140 C- 1% B. 2-methyl-pl1enyl Phenyl amino 180 C 1% B. 2,4-dichloro-phenyl Diphenyl-(4)-nmino 180 190 0 1% A. .(lo 2-diphenyl-ether-(1)-am1no 2% A. 4-chloro-phenyl ZA-dichloro-phenyl-arnino 1% B.

' .do 2,5-1111nethyl-phenyl-amino 1% B. 31. 2,4,5- trlmethyl-phenyl Phenyl-amino 1% B. 3- 4-methyl-phouyl 2-1nethyl-pl1euyl-amino 1% B.

.....d() 2-methoxy-phonylnmino 1% A. d0 4-mcthoxy-phenyl-amino 0.5% B.

4methyl-phenyl 2,5-dimetlxyphonyl-arnino 1% B i-cliloro-phenyl A,S-dimethyl-phenyl-amino 3% B. d 2,5-dichloro-phenyl-amino. 0.5% B

2,G-dimethyl-pl1eny1-amino 1% A.

4-isopropyl-phenyl-amino 1% A.

4-rnethoxy-phenyl-amin0. 5% B.

. 4-chloro-phenyl A-isopropyl-phenyl-amino 3% B. 43 4-methoxy-phenyL- 2,5 dimethyl-phenyl-amii 1% A. 44. 4-isopropyl-phenyL 4-methoxy-phenyl-amino 1% A.

do 4-isopropyl-phenyl-amino. 1 0 A. 46 4-methyl-phenyl 2,B-dimethyl-phenyl-amino 1.3% A. 47- do 2.5-dimethyLphenyl-amino-methyl.- 1.3% A. 48-- do 49. 2,B-Gimethyl-phenyl-omino 3% B. 50. 2,6-din1ethy1-phenyl-amino. 1.5% A. 51 2,4-dimethyl-phenyl-amin0 1.5% A. 51 3,4-dimethyl-phenyl-amino 1.5% A. 53. 3,5-dimethyl-phenyhamino. 1.5% A. 54 2,S-dimethyl-phenyl-amino 4.5% B. 55- 2,6-dimethyl-pheuyl-amino 1.5% A. 561 2,4-dimethyl-phenyl-amino. 5% B. 57 3,4-dimethyl-phenyl-nmino. 1.5% A. 58- 3,5-dimethyLphenyl-aminm 1.5% A. S-methyl-phenyL 2,5-dimethyl-phenyl-amin0 1.5% A. 60.. 2,5-dimethyl-phcnyl 0 4% B.

' 61 3,4-dimethy1-phenyl do 1.5% A.

62 2,4,5-trimethyl-pheny 2-methyl-phenyl-ammo. 3% B. 4-methyl-phenyl 2,4,5-trimethyl-pheny1-arn 4% B 64 4-ethyl-phenyl 2,4dimethy1-phenyl-am1no 2% A.

67- do 2,5-dimethyl-phenyl-am1no 4% B.

69"--. 4-chloro-phenyl Carbazolyl-(3)-ammo 3.0% B+1.8% A.

The invention will be further illustrated by reference to the following specific examples:

Example 1 vformaldehyde. After the light-sensitive coating has been thoroughly/dried by hot air, the sensitized foil is exposed under a transparent negative master, by the contact process, to an l8-amp arc lamp at a distance of about 70 cm. for two minutes. For development of the image formed, the exposed coating is rubbed down with a 2% trisoduim phosphate solution, whereupon the image which previously was barely visible becomes clear. The developed foil is wiped over with a 1% phosphoric acid solution and a yellowish-green positive image is thus obtained from the negative master. The paper foil, which is water-conductive in the parts not covered by the image, is inked up with greasy ink and used as a printing plate. It gives long runs.

The diazo compound mentioned above (Formula 1) is prepared as follows:

3.6 parts by weight of pxylidine and 9 parts by weight f 1-chloro-4-nitrobenzene-Z-sulfochloride are added to 30 parts by weight of water at -95 C. A solution of 2.3 parts by weight of sodium carbonate in 18 parts by weight of water is then slowly added with vigorous stirring. After condensation is completed, the reaction mixture is acidified and the precipitated reaction product is separated by suction filtration while still hot and then washed with water. For purification, the crude reaction product is dissolved in hot, dilute sodium hydroxide solution. The solution is filtered over animal charcoal and the reaction product is reprecipitated by acidification of the filtrate. The melting point is 143-l44 C.; yield is '7080% of theoretical.

A mixture of 3.4 parts by weight of l-chloro-4-nitrobenZene-2sulfonic acid-(2',5-dimethylanilide), 3.4 parts by weight of p-toluene-sulfonamide, 2.2 parts by weight of potassium carbonate, 0.1 part by weight of copper powder and 0.1 part by weight of cuprous chloride is heated for 3 hours with stirring in 9.8 parts by weight of nitrobenzene at 160-170 C. The water formed during the reaction is removed as it is formed by a current of inert gas which is passed through the reaction mixture, and then the nitrobenzene is driven off with steam. The alkaline solution which remains is treated with decolorizing carbon and the condensation product is precipitated therefrom with acid at 90-l 00 C. The compound 1-((4'- rnethyl-benzene-l-sulfonyl) amino) 2-(2,5"-dimethylphenylamino-s-ulfonyl)-4-nitrobenzene is purified by recrystallization from dilute acetone or by Way of its disodium salt, which is sparingly soluble in 2 N-sodium hydroxide solution. After being recrystallized from alcohol, it has a melting point of 178-179 C.; yield is 80-90% of theoretical.

12.2 parts by, weight of the disodium salt of the nitro compound described above are dissolved in 230 parts by weight of 2.5% sodium hydroxide solution and reduced with about 14 parts by weight of sodium dithionite, i.e., a slight excess, at 90-95 C. The reaction mixture is boiled briefly and then separated by suction filtration over charcoal. The amine is precipitated in solid form from the boiling solution by acidification (pH 5-6). For purification, the reaction product is dissolved in boiling methanol, the solution is suction-filtered over charcoal and the filtrate is concentrated until crystallization occurs. After recrystallization from methanol, the melting point is 164 (3.; yield is70-80% of theoretical.

1 part by weight of the amine is dissolved in a mixture of 2 parts by weight of dimethyl formamide and 4 parts by weight of glacial acetic acid, and is diazotized with a slight excess of 40% sodium nitrite solution at 5 C. The d iazotization mixture is stirred and the diazo compound separates out in the form of the iminoquinone diazide. Precipitation is. completed by the dropwise introduction of 14 parts by volume of water. The diazo compound decomposes at 170-175 C.; yield is 90-95% 1.3 parts by Weight of the diazo compound1-((2,4,6"- trimethyl benzene-1-sulfonyl) imino)-2-(4"-inetl1oxyphenylamino sulfonyl)-benzoquinone-(1,4-)-diazide-(4), corresponding to Formula 2, are dissolved in a mixture of 80 parts by volume of glycol monomethylether and 20 parts by volume of butyl acetate, with slight heating. This solution is coated by means of a whirler upon an aluminum foil the surface of which has been mechanically roughened. The coating is dried in hot air and the foil then heated for two minutes to 100 C. to remove residual solvent. The light-sensitive material is exposed under a transparent negative master to an arc lamp and the exposed coating is rubbed down with an aqueous solution containing g. of trisodium phosphate and 3 g. of sodium metasilicate per liter and the image thereby developed. The foil can now be inked up with greasy ink without further treatment. The developed foil may, for example, be set up in a printing apparatus and the greasy ink applied by means of the inking rollers. Positive prints of the negative master used are obtained.

For the preparation of the diazo compound corresponding to Formula 2, 15 parts by weight of 1-chloro-4-nitrobenzene-3-sulfonic acid-(4-methoxy-anilide) are condensed with 17.5 parts by weight of 2,3,5-trimethylbenzene sulfonicacid amide in the presence of 9.7 parts by weight of potassium carbonate, 0.9 part by weight of. copper powder and"0.9 part by weight of cuprous chloride in 150 parts by volume of nitrobenzene at 160-1;65C., in a manner analogous to that described in Example 1. Further processing and purification of the reaction product via the disodium salt of the nitro compound are exactly analogous to the process described in Example 1. After being recrystallized from acetone/ 13 methanol the compound melts at 198-199 C., yield is 70-80% of theoretical.

10.8 parts by weight of the disodium salt of the nitro compound described above are dissolved in 250 parts by weight of 2.5% sodium hydroxide solution and reduced with about 12 parts by weight of sodium dithionite, i.e., a slight excess at -95 C. Animal charcoal is added to the reaction solution, which is then boiled and filtered. When the filtrate is acidified with 10% hydrochloric acid, the amine precipitates out in the the form ofa grey amorphous solid substance; yield is 80-85 of theoretical. The, amine obtained is sufliciently pure for subsequent processing and is dissolved in five times its weightofa mixture of two parts by Weight of dimetlnyl formamide and 4 parts by weight of glacial acetic acid, and is then diazotized with 40% sodium nitrite solution at ,+5 C. The iminoquinone diazide precipitates out in the form of yellow crystals and precipitation is completed by the gradual introduction of 20 parts by volume of water. The melting point is 154-156" C. i

All the other compounds listed in the table are suitable for the preparation of printing plates by the process described in this example.

Example 3 1.5 parts by weight of the diazo compound 1-'( (2',4'- dichloro benzene 1-sulfonyl)-imino) 2-(4-methoxyphenylamino-sulfonyl)-benzoquinone-(1,4)-diazide (4), corresponding to Formula 3, are dissolvedtogether with 1 part by Weight of an alkal-irsoluble novolak, e.g., the phenol-formaldehyde resin commercially available under the trade name Alnovol, in parts by volume of glycol monomethylether. This solution is coated by means of a whirler upon a mechanically roughened aluminum foil and the coating is dried and exposed to light as desribed in Example 2. The developer used is a 1% trisodium phosphate solution and the developed foil is then wiped over With 1% phosphoric acid; a pale yellow positive image of the negative master is obtained which is then linked up with greasy ink. The printing plate thus produced can be used for the preparation of copies in the apparatus commonly used for oflset printing.

The diazo compound corresponding to Formula 3 is obtained by a process analogous to that described in Example 1. p

15 parts by weight of 1-chloro-4-nitrobenzene-Z-sultonic acid-(4-methoxy-anilide) are condensed with 19.80 parts by Weight of 2,4-dichloro benzene-sulfonamide in the presence of 9.7 parts by weight of potassium carbonate, 1.5 parts by weight of copper powder and 1.5 parts by weight of cuprous chloride in 100 parts-by volume of nitrobenzene at 160 C.

The reaction is conducted in a current of nitrogen and vigorous stirring is maintained. The reaction product is further processed as described in Example 1. The 1- ((2',4-dichloro-benzene 1 sulfonyl)-amino)-2-(4- methoxy-phenylamino-sulfonyl)-4-nitrobenzene, after ,being recrystallized from glacial acetic acid, is in the form of a colorless substance with a melting point of 182-183 C.; yield is 70-75% of theoretical.

The corresponding amine is prepared therefrom by reduction with sodium dithionite in alkaline solution. After recrystallization from an acetone/methanol mixture, it is obtained in the fonm of colorless crystals with a melting point of 172-1735 C.; it is diazotized as described in Example 1. A suitable solution for use in the diazotization process is a mixture of 70 parts by volume of dimethyl formamide and 100 parts by volume of g acial acetic acid. The diazo compound precipitates out in the form of yellow crystals which melt, with decomposition, at -155" C.,

- Example 4 methyl benzene-1'-su1fo nyl)-imino)-2-(4' isopropyL phenylamino-sulfonyl) benzoquinone (1,4)-diazidescribed in Example 1. condensed with l-chloro-4-nitrobenzene-2-sulfonic acid-- 7 a vance (4), corresponding to Formula 4, are dissolved in a mixture of 80 parts by Volume of glycol monomethylether and 20 parts by volume of butyl acetate. 0.3 part by weight of a resin-like product obtained by condensation of a phenol-formaldehyde hovolak with chloroacetic acid, e.g., a condensation product obtained from the phenolformaldehyde resin Alnovol and chloroacetic acid by the process described in Example of German Patent No. 1,053,930, is added to this solution. This solution is coated .upon a roughened aluminum foil, and the coated side is dried and exposed under a transparent nega tive master for two minutes to an arc lamp. The image formed is developed with a 1.5% aqueous trisodium phosphate solution and the foil bearing the positive image is immediately linked up with greasy ink and used as a printing plate.

The preparation of the compound corresponding to Formula 4 is analogous to the method described in Example 1. parts by weight of 1-chloro-4-nitrobenzene-2- sulfonic acid-(4'-isopropyl-ani1ide) are condensed with 13.7 parts by weight of 4-met-hyl-benzosulfonamide in 100 parts by volume of nitrobenzene, 5.5 parts by weight of potassium carbonate, 0.82 part by weight of copper powder with 0.82 part by weight of cuprous chloride being added. After the processing of the reaction mixture and the purification of the reaction product, the 1-( (4-methylbenzene 1' sulfonyl)-amino)-2-(4-isopropyl-phenylamino-sulfonyl)-4-nitrobenzene, which melts at 162163 C., is obtained. It is dissolved in 200 parts by volume of 2.5% aqueous sodium hydroxide solution and reduced with sodium dithionite. The free amino compound is obtained from the sodium salt in the form of a colorless amorphous substance by acidification with hydrochloric acid; yield is 8085%.

parts by weight of the amino compound thus obtained are dissolved in a mixture of parts by volume of dioxane and 100 parts by volume of glacial acetic acid and-are diazotized with 1.6 parts by weight of sodium nitrite in 10 parts by volume of water. The diazo compound crystallizes out in the form of yellow crystals which melt at 163165 C. Precipitation is effected by the slow introduction of 300 ml. of water.

Example 5 1 part by weight of the diazo compound 1-((2,4',5'- trimethylbenzene 1 sulfonyl)-imino) 2 (4-"-chlorophenylaminosulfonyl) benzoquinone (1,4) diazide- (4), corresponding to Formula 31, and 0.3 part by weight of a condensation product of Alnovol and chloroacetic acid, described in Example 4, are dissolved in 100 parts by volume of glycol monomethylether. This solution is coated by means of a whirler upon an anodically oxidized aluminum foil. Having been well dried, the now lightsensitive foil is exposed to light under a negative transparent master and developed by rubbing down with a 3% trisodium phosphate solution. Then, the side of the toil bearing the image is wiped over with 1% phosphoric acid and inked up with greasy ink. A positive printing plate whichproduces long runs on the printing machine is obtained.

Instead of the compound corresponding to Formula 31, any of the other compounds corresponding to the general formula above can be used with equal success. Particularly good results are obtained with the compounds corresponding to Formulae 1, 3, 6, 18, 20, 24, 29, 33, 39, and 43.

For the preparation of the diazo compound corresponding to Formula 31, the procedure is analogous to that de- 2,4,5-trimethyl-benzosulfamide is 4'-chloro-anilide. A pale yellow nitro compound is obtained which melts at 192193 C. It is reduced in aqueous alkaline solution with sodium dithionite to the corresponding amine and the amino compound thus obtained consists of colorless crystals which melt at 196-197 C.

20 When this amino compound is diazotized, the diazo compound corresponding to Formula 31 is obtained in the form of yellow crystalswhich melt with decomposition at 177 C. .E i. Example 6 An aluminum foil which has been roughened on both sides is coated with a 1% solution of the diazo compound 1-( (4'-chlorobenzene 1' sulfonyl)-imino)-2-(4"- rnethoxyphenylaminosulfonyl)-benzoquinone (1,4) diazide-( t), corresponding to Formula 6, in glycol mono methylether. The coating is thoroughly dried and for the production of an image the light-sensitive foil is exposed for 6 minutes under a transparent negative master in a copying apparatus commercially available under the trade name Drulyphot which contains, as a light source, a number of fluorescent tubes. For the development of the image, the exposed foil is treated with a 1.5% aqueous trisodium phosphate solution; it is then wiped over with 1% phosphoric acid and inked up with greasy ink so that it may be used as a printing plate.

The preparation of the diazo compound above is by a process analogous to that described in Example. 1. 30.9 parts by weight of 4-chloro-benzosulfamide are condensed with 30 parts by weight of 1-chloro-4-nitrobenzene-Z-suh fonic acid (4'-methoxy-anilide) in 200 parts by volume of nitrobenzene at 1601 65 C., in the presence of 19.4 parts by weight of potassium carbonate, 2.3 parts by Weight of copper powder and 2.3 parts by weight of cuprous chloride. The condensation product obtained is purified by way of the disodium salt, from which the free compound is obtained in an yield, in the form of yellow crystals which melt at 183-184 C. Reduction and diazotization are analogous to the method given in Example 1. A yellow-colored diazonium compound is obtained which melts at 15l-152 C.

Example 7 4 parts by weight of the diazo compound corresponding to Formula 1, 3 parts by weight of the phenol-formaldehyde resin novolak, commercially available under the trade name Alnovol, and 0.5 part by weight of Methyl Violet (Schultz Farbstoiftabellen, 7th edition, vol. .1, (1931), p. 327, No. 783) are dissolved in parts by volume of glycol monomethylether and the solution is coated by means of a whirler upon asmoothed and polished zinc plate. After the coating has been dried in hot air, the now light-sensitive zinc plate is exposed under a transparent negative film master for five minutes to a carbon arc lamp at a distance of 70 cm. The exposed Zinc plate is then wiped over with a 5% aqueous trisodium phosphate solution containing 15% of glycol monomethylether and rinsed down with water. The zinc plate. upon which the positive image of the negative master is now clearly visible in blue on metal ground, is backcoated with asphalt. It is then immersed for 10 minutes in 7% nitric acid, the side bearing the image being treated with a soft artists brush. The zinc plate with the positrve deep-etched image of the negative master is suitable for use as a printing plate.

Example 8 1 part by weight of the diazo compound corresponding to Formula 1, 0.25 part by weight of the diazo compound 1-((4-methyl-benzene-l-sulfonylyimino) 2 (phenylaminosulfonyl)-benzoquinone-(1,4) diazide (4), corresponding to Formula 8, and 0.25 part by weight of the ly roughened aluminum foil by means of a whirler. The

coating is dried in hot air and then heated to 100 'C., for two minutes to drive 01f the solvent completely. The now light-sensitive foil is exposed under a transparent negative master, for two minutes, to an arc lamp at a distance of 70 cm. and the exposed coating is developed with a 2% aqueous trisodium phosphate solution. The side bearing the image is wiped over with 1% aqueous phosphoric acid and inked up with greasy ink. The foil, with the positive image of the negative master, can be used as a printing plate for the preparation of copies. Very long runs can be achieved.

For the preparation of the diazo compound corresponding to Formula 8, 1-chloro-4-nitrobenzene-2-sulfonic acid anilide is condensed with 4-,methyl-benzosulfamide in a manner analogous to that described in Example 1, and a nitro compound, which after recrystallization from methanol melts at 168-169" C., is obtained in 8090% yield. The reduction of the nitro compound is effected in alkaline solution wth sodium dithionite and the amine is obtained in 70-80% yield. After recrystallization from methanol it melts at 173 C. Diazotization then yields the diazo compound corresponding to Formula 8 in the form of yellow crystals which melt at 168-170" C.

The diazo compound corresponding to Formula 10 is obtained in an analogous manner. The condensation process is performed with 1-quinone-4-nitrobenzene-2-sulfonic acid anilide and 4-chloro-benzosulfamide. A pale yellow nitro compound, which melts at 171l72 C., is obtained in 80-90% yield. From this, the amino compound is produced in 60-70% yield and has the formof colorless crystals which melt at 168-170 C; The diazo compound corresponding to Formula 10 is obtained therefrom in 9095% yield by diazotization. It melts, with decomposition, at 163 C.

' Example 9 1.5 parts by weight of the diazo compound corresponding to Formula 58, l-((2-methylbenzene-1'-sulfonyl)- imino) 2 (3,S"-dimethyl-phenylamino-sulfonyl)-benzoquinone-(1,4)-diazide-4, and 0.5 part by weight of a copolymer of styrene and maleic anhydride traded by the company Monsanto Chemical Co. under the trade name of Lustr'ex 820, are dissolved in 100 parts by volume of ethyleneglycol monomethylether. An aluminum foil mechanically roughened on both surfaces is coated with this solution and then dried, as described in Example 2. Subsequently, the light sensitive foil is exposed for two minutes under a transparent master to the light of a carbon arc lamp. By wiping over with a cotton pad soaked in a 5% aqueous trisodium phosphate solution, a printing plate is obtained which produces long runs.

The diazo compound corresponding to Formula 58 is prepared as follows:

1 chloro-4-nitro-benzene-Z-sulfonic-acid-(3',5'-dimethylphenyl)-amide is condensed with Z-methyl-benzosulfamide in accordance with the statements made in Example l,.and an about70% yield of a nitr'o compound is ob- .tained, which, after recrystallization from methanol, melts at 183 C. Subsequently, the nitro compound is reduced with sodium dithionite in an alkaline solution. A yield of 60% of the theoretical is obtained of an amine, which is purified by recrystallization from methanol and melts at 220-22l C. By diazotization the diazo compound corresponding to Formula 58 is obtained in the form of yellow.

crystals which decompose at about 134 C.

This application is a division of copending application, Serial No. 50,317, filed August 18, 1960.

It will be obvious to those skilled in the art that many modifications may be made Within the scope of the present invention Without departing from the spirit thereof, and the invention includesall such modifications.

22 i What is claimed isf 1. A compound having the formula in which R and Y arearyl groups. 2. A compound having the formula H CH3 USOFE 3. A compound having" the formula 5. compound havingflthe formula H OH;

7. A compound having the formula ll H V wsalgm, a l

8. A compound having the formula 9. A compound having the formula 10. A compound having the formula 24' 13. A presensitized printing plate comprising a base material having a coating thereon, the coating comprising a compound having the formula 14. A presensitized printing plate comprising a base material having a coating thereon, the coating comprising a compound having the formula 15. A presensitized printing plate comprising a base material having a coating thereon, the coating comprising a compound having the formula H H CH3 SO 1 l' -(BE 40 a 2 I 16. A presensitized printing plate comprising a base material having a coating thereon, the coating comprising a compound having the formula 11. A presensitized printing plate comprising a base material having a coating thereon, the coating comprising O a compound having the formula in which R and Y are aryl groups.

U-Sm-NQ 17. A presensitized printing plate comprising a base material having a coating thereon, the coating comprising 12. A presensitized printing plate comprising a base a compound having tha formula material having a coating thereon, the coating comprising a compound having the formula II E I sm-NG-orln:a

. 25 material having a coating thereon, the coating comprising a compound having the formula N II 19. A presensitized printing plate comprising a base material] having a coating thereon, the coating comprising acompound having the formula '20. A presensitized printing plate according to claim 11 in which the coating contains an alkali-soluble resin.

21. A presensitized printing plate comprising a base material having a coating thereon, the coating comprising a compound having the formula ILEZ 22. A process for making a printing plate which comprises exposing a coated base material to light under a master, the coating comprising a compound having the formula in which R and Y are aryl groups, and treating the eX- posed coating with dilute alkali developing solution.

23. A process for making a printing plate which comprises exposing a coated basematerial to light under a master, the coating comprising a compound having the formula N 011, II

s Og-N- and treating the exposed coating with a dilute alkali developing solution.

24. A process for making a printing plate which comprises exposing a coated base material to light under a and treating the exposed coating with a veloping solution. t

25. A process for making a printing: plate which com prises exposing a coated base material to light under a master, the coating comprising a compound having the formula 0 its-@411 1 own-Odom I ll dilute alkali: dc"- and treating the exposed coating with a veloping solution.

26. A process for-making a printingplate whichcomprises exposing a coated base material to light under a dilute alkali demaster, the coating comprising a compound having the formula l H OH;

I i SOs-N H I (5H3 and treating the exposed coating with dilute alkali developing solution.

27. A process for making a printing plate which co'mprises exposing a coated base material to light under a master, the coating comprising a compound havingthe formula H: OzS-G-Cfis 1L 47H}; I t H andtreating the exposed coating with dilute Yalkali developing solution. i a

2? 28. A process for making a printing plate which comprises exposing a coated base material to light under a master, the coating comprising a compound having the formula andytreating the exposed coating with a dilute alkali developing solution.

29. A process for making a printing plate which comprises exposing a coated base material to light under ;a master, the coating comprising a compound having the a formula .and treating the exposed coating with a dilute alkali developing solution.

30. A process for making a printing plate which comprises exposing a coated base material to light under a master, the coating comprising a compound having the formula N II t}! and treating the exposed coating with a dilute alkali developing solution.

31. A process for making a printing plate which comprises exposing a coated base material to light under a .master, the coating comprising a compound having the formula and treating the exposed coating with a dilute alkali developing solution.

28 32. A process according to claim 22 in which the coating contains an alkali-soluble resin.

33. A compound having the formula in which R is an aryl group, R is selected from the group consisting of hydrogen, halogen, alkyl and alkoxy groups, X is selected from the group consisting of hydrogen and alkyl groups, and Y is selected from the group consisting of alkyl and aryl groups.

34. A presensitized printing plate comprising a base material having a coating thereon, the coating comprising a compound having the formula III-S 01-11 in which R is an aryl group, R is selected from the group consisting of hydrogen, halogen, alkyl and alkoxy groups, X is selected from the group consisting of hydrogen and alkyl groups, and Y is selected from the group consisting of alkyl and aryl groups, and treating the exposed coating with a dilute alkali developing solution.

36. A compound having the formula N H S s-N- ii. I 1'1 29 30 37. Apresensitized printing plate comprisingabase mamaster, the coating comprising a compound having a terial having a coating thereon, the coating comprising formula 21 compound having the formula Q] and treating the exposed coating with a developing solu- 38. A process for making a printing plate which comprises exposing a coated base material to light under a 20 No references cited. 

22. A PROCESS FOR MAKING A PRINTING PLATE WHICH COMPRISES EXPOSING A COATED BASE MATERIAL TO LIGHT UNDER A MASTER, THE COATING COMPRISING A COMPOUND HAVING THE FORMULA 